Have you done any suspension upgrades or regular maintenance? Replaced the shocks, bushings or anything? Im gonna be putting on springs before too long so I was going to check all my suspension components out while its all apart. Im thinking its the compression rods and maybe bushings on mine.

 

Well im lowered on 350z tein S tech springs. It doesnt sound like suspension though

 

wheel bearing maybe if it happens when you are driving
I know the G35's make sound when you are backing up, but not going forward

 

the compression rod in front he said sound is from rear

 

hmm I have the same problem too, loosing plastics noise in the rear (seem to be either in the trunk or back seat), probably gotta take the rear seats out to check out the braces first

 

Have you done the axle service ? Remove axle shafts and grease the splines going into rear wheel bearings.

 

have you ever changed the differential fluid?

 

i same thing i just put in 1300$ coils and still makes that popping sound im thinking its the End links if you have after market ones you have to adjust them

 

Good luck with that if you have the SPL endlinks............

 

This happens with my car all the time. Still haven't found what it is yet. IMO, its more of a flexing issue with the unibody then a suspension problem.

 

Turned out to be a bad weld in the body panels near the right rear shock tower...Dealership fixed it under warranty by re-inforcing the weld with self-tapping screws back in March - No issues since.

 

I've had this problem for a long time, and the best I can guess is that its the sunroof. I've heard the sunroof rails can make a pop, crack, or creak noise if they are loose. Every time I drive over a speed bump unevenly, or take a slow turn i can hear it. My understanding is it would take a significant effort to remove the headliner and tighten the bolts. Needless to say, i haven't gotten around to it yet.

I hear it behind me in the drivers seat. Anyone in the back can't tell where its coming from.

Hope this helps.